johnstone



3 SheetsSheet 1.

(No Model.)

L. JOHNSTONE. AUTOMATIG FEEDING DEVICE.

Patented Oct. 3:1.I .1893,

//VVNTOR.

IV/TNL'SSE-S.

(No Model.) 3 Sheets-Sheet 2.

L. JOHNSTONE. AUTQMATIGEEEDINGIDEVIGB.

No. 507,910. Patented 00:. 31, 1893.

FIG-3.

I z I /NVNTOR. WW 4% UNITED STATES PATENT OFFICE.

LEWIS J OHNSTO'NE, OF EDINBURGH, SCOTLAND.

AUTOMATIC FEEDING DEVICE.

SPECIFICATION forming part of Letters Patent No. 507,910, dated October31, 1893. Application filed May 22, 1893. Serial No. 5,029. (No model.)Patented in EnglandAugust 20, 1892, No. 15,062.

To all whom it may concern.-

Be it known that I, LEWIS JOHNSTONE, engineer and analytical chemist,asubject of the Queen of Great Britain, residing at 10 St. AndrewsSquare, Edinburgh, Scotland, have invented an Improved Automatic FeedingDevice, (for which I have obtained Letters Pat-- entin Great Britain,No. 15,062, dated August 20, 1892,) of which the following is aspecification.

My invention relates to an improved apparatus for returning into theboiler the water of condensation from coils, steam jackets, heatingpipes, steam drying cylinders, &c., or for forcing ordinary feed waterinto the boiler, or other similar purposes. my present invention may beeasily understood and readily carried into practice I will proceed todescribe same with reference to the drawings hereunto annexed.

Figure l is a general view of an apparatus for returning water ofcondensation into the steam generator from a point below the wafor levelin such steam boiler. Fig. 2 is a similar view of my apparatus foreffecting the same purpose from a point above the water level in thegenerator. Fig. 3 is a vertical (longitudinal) sectional view on line1-1 Fig.4 of the special valve apparatus and its connections accordingto my present invention. Fig. 4 is a sectional plan on line 22 Fig. 3.Figs. 5, 6, 7, and 8 illustratea slightly modified construction of thespecial valveas hereinafter explained.

Similar letters of reference indicate corresponding parts throughout.

A is the steam boiler or steam generator of any usual or suitableconstruction.

13 is the main steam pipeleading to any steam motor, steam jacket coilor drying chamber, or other steam actuated or steam heated device or thelike all of which for the sake of brevity I shall hereinafter refer toas the coil.

O is the coil illustrated by way of example.

D is the outlet from the coilleading into E.

E is. the casing containing the special valve apparatusshown in detailin Figs. 3 and 4 and in Figs. 5 to .7.

F is the branch steam pipeleading from And in order thatv I the mainsteam supply pipe 13 into the easing E.

G is the outlet pipe from the valve casing E-leading to the reservoir H.

H is the lower reservoir (as I term it) in which the water ofcondensation is accumulated ready to be forced into the reservoir J.

I is a pipe leading from H to J.

J is the upper reservoir (as I term it) from whence the water passesinto the generator A.

K is a pipe leading from J into the lower part ('i. (2. below the waterlevel) of generator A.

L is a blow off cock in pipe K.

M is a T-piece or branch pipe leading from D to a third reservoir N.

N is a reservoir where the water of condensation accumulates from thecoil 0.

O is a pipe connecting the lower part of reservoir N with the lower partof the reservoir H.

P is a branch pipe leading from the pipe I to the under side of thesteam piston valve Q in the casing E.

Referring now to the equilibrium or balance valve apparatus shown inFigs. 3 and 4:Q is a large piston valve acting as a tightly fittingpiston or plunger in the cylinder or chamber R which latter mayadvantageously be formed with a bush or lining S as shown. T'll areapertures in the cylinder R controlled by the valve Q and leading fromthe cylinder R to the outlet G through the steam passage way U. U is asteam passage way leading from the pipe F cylinder R and apertures T tothe outlet pipe G and also to the inlet apertures '1" round the secondvalve cylinder W. V is a second and smaller piston valve. W is thecylinder of the second valve V also advantageously lined similar to Rand also having apertures T (or other communication) with the passageway U. X is the piston rod on the piston Q, and X the piston rod on thepiston V, both pivoted to the pivoted lever Y. Z is a fixed supportcarrying the pivoted leverY which latter therefore has its fulcrum on Z.a is aback pressure valve to prevent any return of water from the boilerA into the pipe K. b is a back pressure valve in the pipe I to preventpressure from the pipes K and I and chamber J,

coil 0.

passing back in the chamber 11. c is a back pressure valve to preventpressure from the chamber II or pipe I passing back into the pipe 0.

The automatic operation of the equilibrium or balance valves Q and V isas follows:-The full live steam pressure is constant (when the apparatusis in work) through F onto the top side of piston Q which when forceddownward admits same live steam through the conduits T. U. G. H. I. andP to the under side of the piston Q and thus equal steam pressure willexist on both top and bottom of piston Q and so the latter is broughtinto equilibrium and can then be easily controlled by the second valve Vand their respective connections. The valve V is now at its uppermostposition andon the top side thereof has applied thereto the pressurecoming through D from the The steam valve Q being already inrequilibrium(in its lowermost position)as just-previously explained the leastpressure or force exerted onthe top of V (sufficient to overcomefriction) will force down V to its lowermost position and through thepivoted lever Y and the respective piston rods X and X will therebymoveup the valve Q to its uppermost position while in the case of the valveV as soon as it passes the apertures T steam pressure will be therebyadmitted to the upper side of the valve V. With the valve Q thus at itsuppermost position and the valve V at its lowermost positionthe fulllive steam pressure from B and F remains constant on the top of Q whilethe steam pressure remaining in the parts I, J, K and P is preventedfrom passing back by means of the back pressure valve b and as thissteam pressure dies away in the parts I, J, K and P (by reason ofradiation, condensation or by a spe cial exhaust, &c.), the pressurethrough the pipe P on the under side of the valve Q will decrease andthen as soon as the constant pressure on the top of the valve Q isgreater than the resistance of the valve V plus the remaining pressureunder the valve Q plus friction then the piston Q will be forced downand a fresh charge of live steam suddenly passed through R. T. U. G. H.I. and P and the cycle repeated asbefore. To assist the quick actionofthe balance valve so that immediately the valve Q has begun to move downit shall continue its movement 1'a pidlyI may use what I term a dash-potor regulating device such as illustrated and consisting of a by pass efin the cylinder W as shown in dotted lines in Fig. 3 acting inconjunction with the valve gear beneath the valve V as shown in Fig. 3to automatically permitexhaust from beneath valve V at the desiredmoment; viz: The valve V carries on its under side the extension forminga smaller-plunger g closed at its bottom end It and having openings 2'at its top end and openingsjat its lower part this lower part passingthrough a gland It so that immediately the apertures j in the side wallsof g pass below the closelyfitting part of gland 7c; then the steambeneath valve V is exhausted. The action of this partial equalizing ofthe valve V is as follows:- Assuming the valve V to be at its lowermostposition in the cylinder W it will cover and close the end f of theby-pass and also the aperturesj will lie clear of the gland k andtherefore no pressure will now exist below valve V. As soon as the valveQ is forced down and consequently lifts the valve V against the pressurepipe in D.'then the apertnresj are brought inside of gland 7c andconsequently closed. At the same moment the endfof the bypass isuncovered by the upward movement of the valve V and therefore pressureabove and below valve V will be partially equalized and consequentlypart of the resistance to valve Q at first oifered by valve V is nowsuddenly removed and thereby the-valve Q will perform the rest of itstravel downward at a greatly increasedspeed. On the return movement thatis .when the valve V is moved downward (and thereby lifting the valve Q)the movement of valve V is slow owing to the pressure under valve Vcoming through the bypass ef but assoon as valve V closes f andexhaustion ispermitted at j then no resistance will remain under valve Vand consequently the latter-will perform the rest of its travel at agreatlyaccelerated speed. This arrangement or equivalent will be foundof greatutility especially in cases where great variations may existfromtime to timebetween theboiler pressure and the pressure in pipe ,Dduring the working of the apparatus.

In cases where a great differencenormally exists between the boilerpressure and the pressure in coil 0 and its outlet D-then thisdifference may be compensated for by weighting the end Y of the lever Yor by altering the relative sizes (areas) of the valves Q and V forinstance the latter might be of much larger area than Q-as hereinafterfurther explained.

The operation of the whole apparatusis as follows:-The water ofcondensationfrom the coil C-(or other water to be returned or fed to theboiler A) coming through the outlet D (which may or may not be on adecline for this purpose) passes through the T-piece M and accumulatesin the reservoir N and pipe 0. As soon as the reservoir II has beenemptied of its last charge, steam pressure is equalized in both top andbottom of II by the valve V being forced down (as before described) andthereby whatever steam pressure exists in the pipe .G and reservoir Hwill pass through the parts U T W and D to M and N. Thus pressure beingequalized all through these last named partsthe water accumulated in Nwill now by gravity descending through 0 past the back pressure valve 0and fill or partially fill the reservoir II. I would here remark thatthe parts E. H. J and N and their connections are shown in Figs. 1 and 2on a much larger scale in pro- IIO portion to the other parts of theseFigs. 1 and 2-'this being done for the sake of clearness.

- Figs. 3 and 4 represent the valve apparatus. As soon now as thepressure under valve Q has died away or decreased sufficiently the livesteam in branch steam pipe F will force down valve Q (as beforeexplained) and thereby" the apertures T are uncovered by valve Q and acharge of live steam is delivered from F through the parts R. T. U and Gto the upper surface of the water in the reservoir H which is therebysuddenly driven -out' of the reservoir H and as it cannot escape backthrough'the back pressure valve cit is therefore driven past I) throughthe pipe I to the reservoir J which latter reservoir J is and alwaysmust be placed at a height above the water level in the boiler andshould be of a capacity somewhatlarger than the reservoir H. Having gotthe charge of water up to this elevated position (in the reservoir J)much above the water level in the steam generator A it will thus beeasily seen and understood that, as such water in the elevated reservoirJ will have the full steam pressure from the pipes B and F through thepipe I behind it, the pressure from the boiler at a will beequalized-while the weight of the water in theres ervoir J (that isgravity) will cause the said Water to readily pass through the feed pipeK (past the back pressure valve a) into the boiler A. The live steamsupply to the pipe I lasts a sufficient time to do its work and as soonas same is cut off and the pressure in the pipe I begins to decreasethen the pressure from the steam generator A will close the backpressure valve or and consequently no water can come back from the saidboiler A into the pipe K; and thus as no water from boiler A can comeback past a consequently no water column is thereby formed in the pipeK. Meantime While the pressure has been dying away in the pipe I thefurther accumulation of water in the reservoir N has emptied itself intothe reservoir H and live steam being again admitted to the upper partthereof this charge is driven through the parts I. J and K into theboiler-A and'so on-thewhole cycle being automatic and automatically andperiodically repeating itself so that very large quantities of water canbe by my apparatus steadily returned into the boiler.

It is for the especial purpose of being able I small quantities ofreturn water where very great difference exists between boiler pressureand the coil or feed water and for these and other reasons giving greatadvantages over apparatus previously designed for similar'purposes.

Referring to the modified construction of valve apparatus shown in Figs.5, 6, 7 and 8: Fig. 5'is a horizontal'sectionon the line 33 to V).

Fig. 6. Fig. 6 is a vertical section online 4-4 Fig. 5. Fig. 7 is avertical section on line 55 Fig. 5. Fig. 8 is a cross section online-6-6 Figs. 6 and 7. The letters D. E. F. G. P. and U respectivelydesignate the same parts as in Figs. 3 and 4.

Referring Qto Figs. 5 to 8: q is the steam valve (corresponding to Q).1' is cylinder in which q operates (corresponding to R). s is piston rodon g slotted to receive the end of arm t see Fig. 6. tis arm on the axleshaft tt which arm t is connected to s as'shown in Fig. 6 or in anyother suitable Way. u is axle shaft mounted with glands or stuffingboxes or in othersuitable steam tight manner in the casin g'E. o issecond valve (corresponding '40 is piston rod on v. a: is'arm connectedto to similar tot and also keyedor otherwise fixed to shaft u. y is anarm or lever also fixed at right angles on the shaft uby which means acounter balance may be used or a dashpot attached thereto to control thevalves as desired. .2 z are oil feed cups to keep the internal workingparts of this valve apparatus lubricated It will thus be seen that thevalves q and o arexconnected through the shaft to and connecting arms tand so so that when the valve qis forced down the valve'u is therebyforced up and vice versa.

The operation is as followsg-The full steam pressure coming through pipeFforces down the valve q clear of the passage U whence the steampressure passes as before through G into H. I. J. and K,'while as soonas equal steam pressure-attains at P the valve q is brought intoequilibrium and the pressure at D acting on top of 'u will thereby forcedown '0 and consequently raise q and thus cut ofi steam from F passingto U While as soon as the top of o clears passage U the steam thereinremaining can exhaust back into the 'coil and'at the same time may acton o to accelerate its downward movement.

' The apparatus shown in Figs. 5 to 8 will thus be seen to be verysimple in construction and'action and will be found to work Well incases where the variation between the pressure in F and D is constant orapproxi-- mately constant. Where however the pressure in D is liable togreat variation it willbe found necessary to adopt and use acompensating arrangement such as illustrated in Fig. 3 or in thealternative a greatly increased length ofrise in pipe I so as to give agreatly increased height to J and consequently'increased fall from J toA'as further explained hereinafter.

The advantage of having the bush or lining S in the cylinders R and W(Figs. 3 and 4:) with small apertures T T therein into passage Uis thatsplit piston rings or packing rings may be used on Q and V, whereas inthe arrangement such as shown in Figs. 5 to 8 such packing rings couldnot be used.

Some lap should be given to the steam valve Q or q and also totheequilibrium' or balance ICC valve V or r so that the one closesbefore the other opens and to reduceleakage, the.

It will be readily understood that where the coils are on a higher ordifferent level from the water level of the boiler the proper positioncan be easily found where the above conditions apply. Further theapparatus may be arrangedand mounted at any convenient point (withinpractical limits) more or less distant from the boiler.

W'eightiu g the steam valve against the live 1 steam may-be adoptedandhas several advantagesafor instance as a means of regulating thestroke of the valves and to retard the live steam from acting again tooquickly.

The amount of weight required tobalance thebalance valve of the coiloutlet sidecan naturally be much reduced bymakingsaid valve of smallerdiameter, and this is ofiade size of the outlet valve may be increasedbeyond that of the steam valve so as to be more sensitive to thisverylow pressure. The advantageof thus; making the valve more 101 less selfbalancing as againstthe amount of dead weight required is readily seenbya simple example of calculation.

If the valves are of equal area say one inch, the steam valve being inequilibrium, the boiler pressure sixty pounds and the outlet from coilthirty pounds periinchthe weighting necessary will be thirty pounds orits equivalent by leverage. If however the valve bemade partially selfbalancing say the area of pressure on the under side be made half thaton the upper the amount of weighting will be one half of the formercase, 71. e., fifteen poundsor its equivalent by leverage. Further ifthe area of this valvebe reduced to say half inch area the weightingwithout the self balancing would be fifteen pounds or its equivalent byleverage and with the .self balancing to'the above proportion seven andone-half pounds or its equivalent by leverage. Again the lower pressurearea (on the valve V) may be made three-fourths of the area of the upperso that in the case of the one inch valve the downward pressure would bethirty pounds and the upward three-fourths of thirty (equal totwenty-two and one-half)- that is, the amount of the balance byweighting would be thirty minus twenty-two and one-half. (equal to sevenand one-half) pounds. With the area one half inch the downward pressurewould be fifteen, the upward threefourths of fifteen, equal to (elevenand onefourth;) so the amount to be balanced by dead weight would befifteen minus eleven and removed altogether. boiler pressure of sixtypounds would open one-fourth (equal to three and three-fourths) pounds.The conditions under which this dead weight may be disregarded arereadily seen by studying for a. moment the valve on the steam side, '5.e., the steam driven valve Q. For example take the steam valve of saythree inchesarea as against the last example of the other side whichgave (with thirty pounds pressureat coil outlet) an effective downwardpressure of three and three-fourths pounds. Consider theweight On thesteam side the the valveand steam would pass round to the under side andalso to the upper reservoir but itis manifest that the steam on theunder side cannot rise to the sixtypounds as before, as the valve Qwould be shut ofiby the action of the three and ,three -fourths poundson the other valve V. Now the area of the steam piston Q has been takenat three inches; therefore when the steam on the under side risestosixty minus one-third of three and three-fourths (equal to sixty minusone and one-fourth, equal to fifty-eight andthreefourths) the steamvalve Q will be in equilibrium and as it rises above this the valve Vwill again open to the coil 0. Now as the steam has thereby been shutoff before the boiler pressure was reached a sufficient extra drop fromtheupper reservoir J will have to be allowed (this amounts to weightingthe valve against the live steam.)

It will be readily seen that the larger the steam valve or the greaterits leverage is compared to the coil valve-taking their efiectivepressure areas--the more control has the former over the latter, thiscontrol in the above case amounting to dispensing with the weight on thesteam side; and with the upper reservoir at a sufiicient height thepressure in the coil mayvarygreatly without affecting theaction of thevalve in forcing the water back to the boiler.

As I have. already stated I may use adashpot or other device forregulating. This may be put in the coil side of the valve itself and isshown in Fig. 3 where by a bypass it is effected that when the coilvalve V is closed (1'. e. up) it is in the state of partial equilibriumdescribed butwhen it is open (2'. e. down) it has the full area of thetop pressure only so that the pressure on the steam side has to falllower (below the steam piston) in order that it may allow the steampressure on the top of steam side to open.

In the above case it was shown that when the steam on the under side ofsteam valve was fifty-eight and three-fourths equilibrium full area ofpressure--viz., fifteen poundss0 that the steam has to fall one-third offifteen (equal to five) before equilibrium is established on the steamvalve thus delaying the action of the steam exactly as required.

It will be obvious that my present invention may be carried intopractice and modified in various ways without departing from the natureof my invention -as various details'of construction and arrangement ofparts may be altered or modified according to the varying conditionsunder which my invention may be required to act and as to which any oneskilled in the art or other competent person would be able to decideaccording to the surrounding circumstances.

Having thus described my invention, what I claim, and desire to secureby Letters Patent of the United States, is-

1. In apparatus for automatically returning water of condensation feedor other water into steam boilers having a circuit or continuouspipe'systemconsisting of the main steam supply pipe the coil or steamusing device and the return pipe leading into the boiler below the waterlevel thereof-the combination with and introduction into such circuit orsystem (between said steam using device and the return pipe) of a valveapparatus consisting of a steam valve having direct communication on oneside thereof with and actuated in one direction by the main steam supplyand on the other side thereof communicating with the return pipe andconnected 'to a second and separate valve so that the movement of onevalve causes movement of the other the said second valve havingcommunication with and actuated in one direction by the pressureexisting or remaining in the coil or steam using device substantially inthe manner and for the purposes hereinbefore described. I

2. In apparatus of the character described having a back pressure valvesuch as a close to the inlet into boilerthe' arrangement and combinationtherewith of valve apparatus having a steam valve working in a cylinderconnected on one side of the valve to the full steam supply and on theother side thereof with the return pipe, a steam passage from suchcylinder controlled by said valve and leading to the accumulated waterin a reservoir pipe or chamber such as H interposed be tween said steampassage and the return pipe, and acting in conjunction with a backpressure valve such as 0 so that such water is driven by such steamthrough the return pipe and higher reservoir J substantially in themanner and for the purposes hereinbefore described. I

3. In an apparatus of the character described, the combination with asteam gener ator and a feed water supply, of a valve apparatusconsisting of a steam valve with live steam connection to the generator,and a second valve moving synchronously with and in reverse direction tosaid steam valve, and connected to the feed supply, reservoirs connectedto each other and to said.valves,-back pressure valves between saidreservoirs, a feed pipe connecting the last reservoir and the steamgenerator, and a back pressure valve in said feed pipe, substantially asand for the purposes described, w I

4. In an apparatus of the character described, the combination with asteam generator and a feed water supply, of a valve apparatus consistingof a casing provided with connections to the generator and to the feedsupply, two valves mounted in said casing .andadapted to movesynchronously, the said valves being provided with ports and connectingpassages, substantially as shown; a reservoir H beneath said valvecasing, and connected to each of said valves; a reservoir N connected tosaid feed supply and to one of said valves; a reservoir J connected tothe other of said valves and to the said generator, the said reservoir Jbeing at a higher level than the Waterin said generator; and backpressure valves between each pair of said reservoirs and between saidreservoirs J and said generator, substantially as and for the purposesdescribed. I

5. In an apparatus of the character described, the combination with asteam generator, a steam using device and meansof condensing the steamused in said device, of a valve apparatus consisting of a steam valvewith live steam connection to the generator, andasecond valvemovingsynchronouslywith and in reverse direction to said steam valve andconnected to the exhaust, reservoirs connected to each other and to saidvalves, back pressure valves between said reservoirs, a feed pipeconnecting the last reservoir an the steam generator, and a backpressure valve in said feed pipe, substantially asand for the purposesdescribed.

6. In an apparatus of the character described, the combination with asteam generator, a steam using device, and means of condensing the waterused in said device; of a' valve apparatus consisting of a casingprovided with connections to the generator and to the exhaust, twovalves mounted in said casing and adapted to move synchronously, thesaid valves being provided with ports'and connecting passages,substantially as shown; a reservoir H beneath said valve casing andconnected to each of said valves; areservoir N connected to said exhaustand to one of said valves, a reservoir J connected to the other of saidvalves and to said generator, the said reservoir J being at a higherlevel than the water in the said generator, and back pressure valvesbetween each pair of said reservoirs and between said reservoir J andsaid generator, substantially as and for the purposes described.

LEWIS J OHNSTONE. Witnesses:

HENRY BIRKBECK, 34 Southampton Buildings, London, England.

THOMAS LAKE, 17 Gracech urch Street, London.

